Petri Net Modeling of Spatial and Temporal Constraints in Track Allocation Problem at Railway Stations

Abstract

The track allocation problem (TAP) at a multi-track, multi-platform mainline railway station is defined by the station track layout and service timetable, which implies combinations of spatial and temporal conflicts. Feasible solutions are available from either traditional planning or advanced intelligent searching methods and their evaluations with respect to operational requirements are essential for the operators. To facilitate thorough analysis, a timed Colored Petri Nets (CPN) model is presented here to encapsulate the inter-relationships of the spatial and temporal constraints in the TAP. The relationships among the static station track layout, TAP solution and the available buffer times are described by the model and it allows systematic representation of train movement at stations and hence analysis on TAP solutions upon service disturbances.